New feature - Enable Menu

Sometimes I need to turn f.lux on for 1-3 hours and the only walk around for it is to change the wakeup time, which is inconvenient and messes up the functionality of the app if I forget to reset it back to the original settings.

It'll be useful if there would have been another menu called Enable that does just like the disable menu but the opposite - turns f.lux on for a predefined/custom amount of time, to a selected temperature/color.

On the same token, why isn't there an option to Disable f.lux for a custom amount of time? 1 hour is not always enough and Until Sunrise can be too much at times.